Ship&#39;s form



es. 3, 1935. E. R. F. MAIER 2,023,236

SHIP 5 FORM Filed 1952 Fay 7 o 1 2 3 4 5 e 7 8 9 m E l k i i 2 J r Patented Dec. 3, 1935 Ul'l STATES PATENT OFFICE SHIPS FORM Erich R. Maier, Bremen, Germany Application October 6, 1932, Serial No. 636,507 In Germany October 8, 1931 9 Claims.

:mum of friction and resistance permitting the layers of water to flow along the shortest possible path.

In accordance with the present invention the half frames of the ship are hyperbolas, preferably symmetrical hyperbolas, that is to say, hyperbolas the asymptotes of which are at right angles to one another. However ordinary hyperbolas may also be considered, the asymptotes of which include an obtuse angle with one another. In a ship constructed in this manner the plane of the main diagonal of each side of the hull form intersects the hull form along a mathematically fixed trajectory, that is to say a trajectory which is at right angles to the individual frames. Moreover, according to the present invention the vertices of the hyperbolas of all of the half-frames at each side of the hull form he on the main diagonal and a medial group of the half-frames at each side of the hull form have asymptotes which are identical with each other andwhich preferablycoincidewith the side wall and the base line of the hull form, while from said medial group of half-frames towards the ends of the hull form the vertices of the hyperbolas of the half-frames at each side of the hull form are disposed progressively nearer the medial vertical plane of the hull form and the hyperbolas of the last mentioned half-frames have asymptotes defining included obtuse angles which progressively increase in obtusity towards the ends of the hull form. This, as will be explained later, is a very suitable form for the attainment of the least frictional resistance, since the layers of water in the immediate neighborhood of the skin of the ship take substantially, the shortest path. Accordingly, the water layer in immediate contact with the body of the ship which give rise to the frictional resistance flow in the shortest path from the fore to the aft part of the ship, resulting in turbulence being almost entirely avoided. It is well-known that ships, which for example have frames of the normal full bulging type exhibit very complicated streaming characteristics, whereas on the other hand, in the case of ships models made in accordance with the construction herein set out, the paths of flow are exceptionally simple in their form and the corresponding resistance curve is also very favorable.

On the drawing, on which, by way of illustration, an embodiment of the invention is shown Figure 1 is a partial body end view showing the new construction, while Figure 2 shows the contour of the construction water line and a corresponding development of the bilge diagonal.

Figure 3 is a view illustrating the stem and stern shapes.

The half body view shown in Figure 1 is intended for the aft body of a ship considered without attachments. It could however, equally Well apply to the fore body of the ship. The line MC designates the vertical middle plane of the hull form, while MB designates the construction water line and G0 a line parallel thereto which can be termed the base line. BO runs parallel 15 to MC, and indicates that the medial portion of the side wall of the hull form is parallel to the longitudinal axis or middle plane MC thereof. The actual water line of the ship can obviously lie above or below the construction water line. For the geometrical construction of the individual frames, that is to say, the portions of symmetrical hyperbolas, the following is necessary: First,the displacement curve which is most favorable for the particular hull to be constructed is ascertained, (see curve VO of Figure 3). From this curve the points of intersection Ml, Ml, Mll-Mll', etc., of the hyperbolas of the respective half-frames a, a2, etc. with the plane of the construction water line MB and the vertical medial plane MC of the hull form, as well as the points of intersection of the vertices of the hyperbolas of the half-frames with the main diagonal MO are accurately laid down. The straight lines OB and 0C are the asymptotes of the series of hyperbolas. The vertices of these hyperbolas and also the foci thereof all lie on the main diagonal MO which from a purely geometrical point of view is the X-axis of the hyperbolas While the Y-axis is perpendicular thereto 40 passing through the point 0. In Figure 2 there is shown on a distorted scale the course of the construction water line ml, the ordinates being drawn in on the same scale as in Figure 1, but the distances between the half-frames being very much shortened. In the same figure the bilge diagonal is shown by the curve XX which in the ordinates has the same scale as in Figure 1. Figure 3 shows on a very much smaller scale the contours of the stem and stern corresponding to 0 Figure 1. Obviously, these contours only apply to the construction water line which in this case, is made to coincide with the actual water line, while the extreme low and stern frames above water are considerably closer together in order to give a bluffer form and to prevent a very great overall length which would render the construction more expensive. In Figure 1, in addition, the trajectories NI, N2, N3, N4 are drawn, which trajectories together with the main diagonal or main trajectory MO intersect the hyperbolic frames in each case at right angles. Along these trajectories as above stated flow the water layers with exceptional freedom from disturbance. Obviously, the medial series of hyperbolic half frames can be filled out to such a degree that the branches of the.

hyperbolas finally lie very close to their asymptotes. In the aft body the attachments in the form of stem tubes, screws, rudder and the like are mounted in such a manner as to disturb as little as possible the mathematical contour of the hyperbolic half frames.

Although advantageously the frames both in the fore and aft body of the ship are intended to be hyperbolas also, only a part construction of the frames as hyperbolas falls within the scope of the invention. Thus, the frames may only form hyperbolas in the after body of the ship or only in the fore body of the ship. In particular the latter case where only the frames of the fore body of the ship are hyperbolas will in practice be of importance, the frames of the remaining body of the ship and in particular the aft body of the ship having the normal or any other form.

I claim:

1. A ships hull having a central, vertical plane, a load water line plane, and a main diagonal plane substantially bisecting the angle between said first mentioned planes, said hull further having hyperbolic half-frame sections equally spaced apart longitudinally of the hull and disposed with their vertices and ioci on said main diagonal plane, the hyperbolas of said half-frame sections progressively increasing in obliquity from the hull midsection of maximum width toward the ends of the hull, whereby the path of flow of water from end to end of the hull is of minimum length for a given length of hull.

2. A ships hull having a central, vertical plane, a load water line plane, and a main diagonal plane including the intersection of said first mentioned planes and extending between said first mentioned planes at an angle in the neighborhood of forty-five degrees to said central vertical plane, said hull further having hyperbolic half-frame sections equally spaced apart longitudinally of the hull and disposed with the vertices and foci of their hyperbolas on said main diagonal plane, the hyperbolas of said half-frame sections progressively increasing in obliquity from the hull midsection of maximum width toward an end of the hull, whereby the path of flow of water between said end of the hull and the midsection thereof is of minimum length for a given length of hull between said end and said midsection.

3. A ships hull having a central, vertical plane,

a load water line plane, and a main diagonal 5 plane including the intersection of said first mentioned planes and extending between said first mentioned planes at an angle in the neighborhood of forty-five degrees to said central, vertical plane, said hull further having a midsection of maximum width and end sections of progressively decreasing width from said midsection toward their ends, and hyperbolic halfframe sections equally spaced apart longitudinally of the hull and disposed with the vertices and foci of their hyperbolas on said main diagonal plane, the series of half-frame sections within the length of the midsection of the hull being of symmetrical hyperbolic shape and the asymptotes of the hyperbolas of said series of half-frames being disposed at substantiallyright angles to each other, and the series of half-frame sections between said midsection and at least one end of the hull having hyperbolas of greater obliquity than the hyperbolas of the frames within the length of said midsection and which progressively increase in obliquity from said midsection toward said end of the hull, whereby the path of flow of water between said end of the hull and said midsection and along the latter is of minimum length for a given length of hull including said midsection and said end.

4. A ships hull construction as specified in claim 1, in which said hyperbolic half-frame sections are used only in the fore-part of the ship.

5. A ships hull construction as specified in claim 1, in which said hyperbolic half-frame sections are used only in the aft-part of the ship.

6. A ships hull'construction as specified in 40 claim 1, in which said hyperbolic half-frame sections are used only in the foreand aft-part of the ship.

'7. A ships hull construction as specified in claim 1, in which the hyperbolas of said hyperbolic half-frame sections have a common pair of asymptotes.

8. A ships hull construction as specified in claim 1, in which the hyperbolas of said hyperbolic half-frame sections have a common pair 5 of asymptotes coinciding or extending parallel with the bottom line and side line respectively of the ship.

9. A ships hull construction as specified in claim 1, in which the hyperbolas of said hyperbolic half-frame sections have a common pair of asymptotes disposed at substantially right angles to each other.

' ERICH R. F. MAIER. 

